in depth rear disc brake conversion (2 Viewers)

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I can't get that nut off. I torqued on that sucker with a 27 MM impact socket and a long wrench. I soaked it with PB blaster for 2 days. Should I heat it up?:o

Alternatively, I guess I will have to remove the MC and put it in a vice. I have never removed an MC before, so my question is are there any "gotchas," or is it straight forward 4 bolts.:meh:
master.webp
 
i did not notice the year of your truck until i saw a pic of your booster. diff than mine. i would confirm with someone else with similar setup as you. i am no expert. anyone have any ideas? wheres poser he knows this stuff. hes my go to guy
 
I can't get that nut off. I torqued on that sucker with a 27 MM impact socket and a long wrench. I soaked it with PB blaster for 2 days. Should I heat it up?:o

Alternatively, I guess I will have to remove the MC and put it in a vice. I have never removed an MC before, so my question is are there any "gotchas," or is it straight forward 4 bolts.:meh:

Pighead is right - providing you have the '71 OEM style master cylinder on there, you should have removed the residual valve for the front circuit already when you put the front disk brakes in, need to remove the rear residual valve when you put rear disks in - you will also need a proportioning valve in the rear circuit (which may or may not be that black thingie mounted to your booster ?)

put a vise on the master cylinder to hold it in place and crank some more on the nut

BTW, your fluid reservoirs look seriously depleted :confused
 
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Rear disk conversion question

Hi DSRTRDR,

I am doing the front and back at the same time and the reason for no fluid. I decided to go with a new MC FzJ80 PN 4720160551. Do you know if I will be OK just to bolt bolt the new one right on? I do have a willwood proportioning valve. Will I need to do anything with the booster?
brake 001.webp
 
Rear Disk Brake conversion

I bought the rear kit from poser and everything looks great. Super easy. Question on the hardware: In the box with the calipers came extra brass washers. However, on the hardware line provided in the kit, there are already brass washers - do I use the extra as well that came with the calipers?

Wanted to provide a recient update to this post. You don't need to use the extra brass ring. The 2 on the banjo (top and bottom) are enough.
rear brake HW question.webp
 
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Done with the brakes, now just need to mount the MC and figure out how to secure the rear brake lines. Hose clamp? When you put the brackets and spacers on, be sure to have the longer part of the bolt going outward, this will leave enough room to work with the banjo and brake line. As you can see, mine are backwards so I had to reverse one.
brake finish 001.webp
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brake finish 003.webp
 
Trying to bleed them now and I have the rear passenger open, but I am not getting any fluid to come out of the MC into the lines? Any advice, I thank you in advance.
brake trouble.webp
 
Sorry everyone, I need to do some bench bleeding to prime the master. :doh:
 
This is bench bleeding. Basically take brake line and run it into the MC res. Don't let the fluid drop below the level of the brake lines. Pump slowly to avoid making a mess. You should see bubbles coming from the brake lines. Once there are no more bubbles, QUICKLY remove the dummy lines and attach the main lines. Ypu could even put those rubber pieces from the packaging back onto the MC to avoid air getting into the MC. The idea is just to try to avoid getting air into the system.
brake trouble 002.webp
 
good work

i like that brake cylinder, maybe i need to upgrade that as well on mine
 
Hard Brake Lines

I see you are running the hard line over the top of the spring.

I was planning on running mine to the spring and then using custom rubber brake lines to go from the caliper to the hard brake line.

Is the hard line secure enough as you have it run?
 
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I'm going to buy my kit from Poser but have a question regarding the master and booster. I already have the Geo Metro setup in place. Will it support all the disk brakes?
 
What bore size does the master have?

Don
 
I just looked online and it says 13/16

I have front and rear discs, but it has been several years since I did mine. It seems to me that the master I used had a 1" bore. If I remember correctly the MC was for an 80 series with front and rear discs.

13/16ths seems small to me.

Do some searching to see what you find about the bore size for discs.

Don
 
how do you release the inner axles?

I have a stock rear diff how do you release the inner axles? I read the thread but there's no clear pic or description of how to remove them. Thanks for your help!
 

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